public void Check26ReplaceTagsOk()
        {
            using (var db = new SampleWebAppDb())
            {
                //SETUP
                var snap = new DbSnapShot(db);
                var firstPost = db.Posts.First();
                var tagsNotInFirstPostTracked = db.Tags.Where(x => x.Posts.All(y => y.PostId != firstPost.PostId)).ToList();

                //ATTEMPT

                db.Entry(firstPost).Collection(x => x.Tags).Load();
                firstPost.Tags = tagsNotInFirstPostTracked;
                var status = db.SaveChangesWithChecking();

                //VERIFY
                status.IsValid.ShouldEqual(true, status.Errors);
                snap.CheckSnapShot(db, 0, -1);
                firstPost = db.Blogs.Include(x => x.Posts.Select(y => y.Tags)).First().Posts.First();
                firstPost.Tags.Count.ShouldEqual(1);
            }
        }
        public void Check25UpdatePostToAddTagOk()
        {
            using (var db = new SampleWebAppDb())
            {
                //SETUP
                var snap = new DbSnapShot(db);
                var badTag = db.Tags.Single(x => x.Slug == "bad");
                var firstPost = db.Posts.First();

                //ATTEMPT
                db.Entry(firstPost).Collection(x => x.Tags).Load();
                firstPost.Tags.Add(badTag);
                var status = db.SaveChangesWithChecking();

                //VERIFY
                status.IsValid.ShouldEqual(true, status.Errors);
                snap.CheckSnapShot(db, 0, 1);
                firstPost = db.Blogs.Include(x => x.Posts.Select(y => y.Tags)).First().Posts.First();
                firstPost.Tags.Count.ShouldEqual(3);
            }
        }